DE10129948A1 - Drill, osteotome and their use - Google Patents

Abstract

Drill (1), especially for drilling bone for preparation for insertion of a dental prosthesis. The drill is inserted in a drill head that is equipped with drive and cooling means. The drill has an outer drill tip and an inner coaxial feeler tip (3) that is interlocked with the outer drill tip. The feeler tip can be extended outwards in an axial direction from the drill tip. <??>The feeler tip is acted upon by a force and if the force is less than a threshold value its extends outwards from the drill tip and is decoupled from the rotational motion of the drill tip. <??>An Independent claim is made for an osteotome for the non-destructive removal of a tissue layer from bone tissue from the bone side outwards after drilling through of the bone.

Description

The present invention relates to a drill, in particular Implant bed pre-drill, according to the preamble of claim 1 Osteotome according to claim 11 and their use according to the Claims 26, 27 and 28.

For the purposes of the present invention, the term "proximal" understood "patient side". The term "distal" is meant to "Operator side" mean.

The present invention further relates to the field of Dental prosthetics, especially the insertion of dental implants in existing tooth gaps.

Often, the insertion of dental implants in the upper jaw affects Positions with little bone around the implant anchored securely and permanently. This is particularly the case with Positions in which the roots of the original own Teeth are covered by the maxillary sinus. As a method of surgery has established itself here to reduce the lumen of the maxillary sinus and to extend the implant bed into the maxillary sinus. In the state of Technology becomes, for example, the following cursory described osteotome sinus floor elevation as surgical Procedure applied:

The prerequisite for an osteotome sinus floor elevation is in the Usually a minimum distance of 5-6 mm between the alveolar ridge and Sinus floor in the area of the future implant position. To Local anesthesia becomes a vestibularly stalked mucoperiosteal flap (Gum distance incision) is mobilized and the bone structure becomes exposed.

To achieve a prosthetically optimized implant axis is common a drilling template, e.g. B. Surgical template / CT rail used. This facilitates the marking of the prospective implant location with a 2 mm round bur. With a spiral pilot drill of 2 mm in diameter then becomes the primary preparation the bone cavity started up to approx. 2 mm in front of the sinus floor.

The further formation of the implant bed takes place on the proximal End stamp-shaped ascending osteotomes Diameters. The osteotome becomes cone-shaped tapering, stamp-shaped working end (proximal end) with z. B. 2.2 mm diameter inserted in the prosthetically correct axial direction and with weak hammer blows until the apical stop promoted. The instrument is then rotating Withdrawn movements.

Further processing takes place consecutively with osteotomes increasing diameter to the corresponding bone depth. The the perfect coordination of the instrument diameters enables this Operator a guided preparation process. Are common Length markings placed on the osteotome, which a Secure controlled expansion of the implant bed cranially. First with the final osteotome, e.g. B. with an instrument diameter 2.7 / 3.2 mm with an implant diameter of 3.75 mm the compacted bone structure with the sinus floor in the form of a Greenwood fracture elevated cranially. The Sinus mucosa (Schneiderian membrane) remain intact.

Subsequently, several times in the bone shaft Augmentation material with the appropriate osteotome carefully advanced cranially and condensed. The end position the surgeon notices when there is a slight elastic resistance feel it.

Then, for example, in the prepared bone bed screwed-in implant or a cylindrical or tapped in conical implant. After covering the implant with a cover screw becomes a tight soft tissue seal performed.

A sinus lift curette from STOMA [STOMA Dentalsysteme GmbH & Co KG, Emminger Strasse 39, D-78576 Emmingen-Liptingen] is also known for detaching the sinus mucosa from the bony floor of the maxillary sinus, which is shown in FIG. 1. In addition, spoon-shaped instruments are used to remove and displace the sinus mucosa with extreme caution.

Dentists would like to have more dental implants if needed deploy. However, many are afraid of the possible complications back, which lie mainly in the fact that the Implant bed drill the (safe in terms of drilling technology) Bone area leaves and anatomical soft tissue structures injured. These injuries can include linings in particular of body cavities, such as the Schneiderian membrane of the maxillary sinus (maxillary sinus), nerves and vessels.

A special problem and high demands on the Skill of the surgeon represents the manufacture of the Bone canal to the maxillary sinus floor without the wafer-thin lining of the maxillary sinus when drilling or is also penetrated by means of the osteotome, as a rule not can be worked under sight. Occurs despite all caution and Experience of the surgeon nevertheless a perforation of the Schneider 's membrane, components of the Mixed sinus flora in the bone area, leading to later Inflammation of the bones can result. On the other hand, there is a risk that the base material, usually made of a mixture artificial bone, own bone and if necessary Own plasma, which is to form the later implant bed, the Implant not or not sufficiently on the maxillary sinus is held.

Because of this risk of complications, the prior art developed complex and expensive navigation systems which Surgeon using the detour using computer tomograms Reference keys, which are laser-based and / or holographic convey information about the position of the drill simultaneously. On the one hand, these systems are very expensive (between 100,000 and 1 000 000 euros) and on the other hand are not suitable for another Eliminate problem:

Frequently, the dentist finds out in the areas where an implant insertion would be desirable for prosthetic reasons, an inadequate one or only due to complications Appropriate bone offer.

• a) externen Sinuslift und dem
• b) internen Sinuslift.

For example, an implant can often only be placed in the posterior upper jaw if the maxillary sinus is reduced. The wafer-thin inner lining of the maxillary sinus, the Schneiderian membrane, is detached from the bone with extreme care using appropriate spoon-shaped instruments and displaced. The additional space gained is filled with a mixture of artificial bone, autologous bone and possibly autologous plasma that is layered around the part of the implant protruding into the maxillary sinus. Here one differentiates between the

• a) external sinus lift and the
• b) internal sinus lift.

With the external sinus lift, the envelope folds into the Maxillary sinus sidewall cut out a window to the side is pivoted and thus granted access to the above to be able to carry out the manipulations described. The scope of this intervention means great post-operative Burden on the patient.

With the internal sinus lift already explained at the beginning, the key is felt Surgeon using an implant bed drill to the bottom of the Maxillary sinus. The navigation systems mentioned above can support up to this point, but provide for the rest Action is no further help.

• 1. Die Corticalis besitzt eine größere Knochendichte, welche größeren Druck zur Überwindung erfordert.
• 2. Dieser erhöhte Widerstand bricht plötzlich weg, wenn der Bohrer diese Schicht durchdringt.
• 3. Die Anforderungen an die Reaktionszeit des Operateurs sind sehr hoch, um den plötzlich verringerten Gewebswiderstand zu spüren und den Bohrer rechtzeitig zurückzuziehen.
• 4. Selbst bei ausgezeichneter Reaktionszeit des Operateurs kann es dieser häufig nicht schaffen, auch die Drehbewegung des Bohrers so schnell zu beenden, daß sich dieser nicht aufgrund des Drills von alleine nach vorne ziehen würde.

Thus, even if the location of the breakthrough through the corticalis is precisely known, the drill can "break into" the maxillary sinus and penetrate the maxillary sinus mucosa, as several disadvantageous factors meet at this critical point:

• 1. The corticalis has a greater bone density, which requires greater pressure to overcome.
• 2. This increased resistance suddenly breaks away when the drill penetrates this layer.
• 3. The demands on the response time of the surgeon are very high in order to feel the suddenly reduced tissue resistance and to withdraw the drill in good time.
• 4. Even if the surgeon has an excellent response time, the surgeon is often unable to stop the rotary movement of the drill so quickly that the drill would not pull forward due to the drill.

Under the surgical procedure mentioned at the beginning as an example the surgeon presses in using osteotomes successful preparation of a bone canal by the corticalis, cancellous bone and maxillary sinus Corticalis the Schneiderian membrane from the bone without this tear. This takes place without a direct view and therefore requires great instinct when using 'the relatively large Forces that are necessary to leftover bone and maxillary sinus lining solve and move far enough. You can sharp-edged pieces of bone or even the largest osteotomes To destroy the operator's due diligence.

Navigation systems, e.g. B. "RoboDoc", "NewTom DVT 900011", "med 3 D" "Hip Nav", ("Sim / Plant") etc. can - as above described - the surgeon simultaneously a report on the Location of the drill, however, are next to the high ones Acquisition costs are not suitable to master the problems, which occur when the surgeon drills one Wants to create a connection from the denser to the less dense medium, but does not want to penetrate too far into the less dense medium.

The Schneiderian membrane is used in the relatively young Surgical technique of the internal sinus lift with the implant shape adapted osteotomes, which are rounded at the working ends or stamped at the same time as the preparation of the surrounding bone detached.

The detachment process can be carried out after the Filling also with the advance when placing the implant be continued.

An antroscopic control of this process is possible. there is a fiber optic, for example over the natural ostium, inserted into the maxillary sinus and the bulging of the Schneider's membrane observed.

From facial plastic surgery it is called "blow." known fractures, balloon-like aids into the maxillary sinus bring in, which are filled with plastic materials. Such "blow out" fractures arise when applied to the eyeball suddenly strong pressure is exerted, for example at Punches on the eye, at tennis or golf balls, which meet the eye. The eyeball in turn exerts pressure on the bony eye socket, mostly the weakest point, namely the floor, which is also the ceiling of the maxillary sinus, gives way. The eyeball goes deeper and the patient sees everything twice.

Therapeutically, the bone fragments that cover the bottom of the Form the eye socket again so that both eyes can be repositioned are back on the same level.

This is usually done from the nasal cavity to the maxillary sinus Access created through which a balloon enters the maxillary sinus can be inserted and filled, which to the bony Healing remains and is then removed again.

In the favorable case of a greenwood fracture (i.e. a fracture of the Orbital floor, where the maxillary sinus lining does not tear, but still encloses the breaking point) the intact one is also here Schneiderian membrane moves, but to enlarge the artificially reduced maxillary sinus to her due to the accident original size to return the bone fragments to their to keep old place.

Based on the prior art of those described above It is surgical techniques for implanting dental implants therefore the object of the present invention, an instrument for easier and safer implantation in anatomically critical areas, such as in the area of the To provide the maxilla near the maxillary sinuses.

This task is characterized by the characteristics of the Claim 1 regarding a pilot drill solved.

This task is also solved by an osteotome Claim 10 and the uses of the invention Implant bed drill and osteotome according to claims 26 and 27th

By using a two-part drill, the tip of which is always if it encounters a less dense medium, continue to move penetrates as the rest of the drill body and from the rotary movement can be decoupled, is preferably via a corresponding Evaluation system recognized and this causes the immediate stop the rotational movement by interrupting the motor power supply and Braking.

The dentist can now decide whether to use the Wants to continue drilling. He can use the new system Adjust circumstances, what with the higher value Embodiments is possible, or simply bridge.

Thus, by abandoning the positive fit of the drill bit and Drilling body during the drilling process the advancement of the tip over the Location of the drill body also take place, which according to the invention is used to control a corresponding sensor system, which then switches off the drive electronically. So will ensures that the surgeon when preparing one for one Dental implant insertion required bone channel to the floor the maxillary sinus can be done without the highly sensitive razor-thin Schneiderian membrane or even to penetrate.

The invention relates in particular to a drill, in particular an implant bed pre-drill, for milling bones in preparation for the insertion of dental implants, which is provided as an insert in a drill head equipped with drive and coolants, wherein
the drill has an outer drill tip and in the interior of which a coaxially mounted sensor tip is arranged, which is non-positively connected to the rotatable outer drill tip;
the probe tip can be pushed out in the axial direction from the tip of the drill;
a predetermined adjustable threshold force is applied to the probe tip; and
the sensor tip emerges from the outer drill tip when the resistance force falling below the threshold force falls below and is thereby decoupled from the rotational movement of the outer drill tip.

A preferred embodiment of the drill according to the invention is characterized in that the probe tip with the outer Drill tip via an external / internal hexagon plug connection is non-positively releasably connected.

It is particularly preferred if the sensor tip is attached to that End, which is connected to the outer drill tip Has an external hexagon and inside the outer drill tip corresponding hexagon socket is provided.

In the drill according to the invention, the threshold force of Sensor tip by means of pressurization using a fluid take place, for example a liquid, in particular can be physiological saline.

The pressure is preferably applied by means of a Piston pump.

It is also advantageous that on the drill according to the invention at least one sensor device for detecting the current state the pressure within the fluid inside the outer drill bit is provided.

In a preferred embodiment, the drill can Have circuit which one of the sensor device detected pressure drop registered and operated a switch that the The drill drive switches off and / or brakes. This will in the event of reaching a zone of lower bone density the Drilling process stopped immediately, so that it is avoided that the Surgeon with the drill into the maxillary sinus, so to speak "slips in" and thus penetrates the Schneiderian membrane becomes.

It is particularly convenient for the surgeon if the drive motor for the drill and / or the motor for pressurizing the Sensor tip, in particular piston pump motor, in particular can be remotely controlled using a foot switch.

For additional simultaneous monitoring, it is advantageous if the Threshold force and the actual state of resistance on one Display device, in particular a monitor, are shown, because in addition to feeling the operative Situation, an additional visual control option is available stands. A graphic display is used in particular for this purpose, which in addition to the preset threshold force also the current actual state of the bone tissue resistance reproduces graphically.

The present invention further relates to an osteotome for the non-destructive detachment of a layer of tissue from a bone tissue from the bone side after penetration of the bone, with:
a distal part for guiding the osteotome;
a proximal part for detaching the tissue layer; such as
a middle part that separates the distal part from the proximal part.

Such an osteotome is preferably used to over a prepared the drill and implant bed drill according to the invention The Schneiderian membrane of the bony canal Maxillary sinus floor (corticalis of the maxillary sinus) without detaching hurting them or even penetrating them.

A preferred osteotome is characterized in that the distal part of a handle, in particular a roughened handle, is preferably an angled handle.

An advantageous osteotome is characterized in that the proximal part at an angle of approx. 90 ° to the longitudinal axis of the middle plate is arranged, which is eccentric on the middle part is attached. The is in the insertion state Plate on the cross-sectional area of the middle part of the osteotome and is used for the working position by means of an eccentric axis Expanded the diameter of the middle part and can with the distal part by 360 °. This ensures that due to the eccentric arrangement of the plate a larger one Area of the Schneiderian membrane can be detached than that actual plate area corresponds.

In addition, there is a better pressure distribution.

Further advantageous embodiments of the invention Osteotomes have a plate on the middle part it is appropriate that its outer diameter is at most as large as like the outside diameter of the middle part to get it in with minimal diameter through the prepared bone canal slide.

It is also preferred that the plate is convex proximally is formed, which creates the risk of injury for Schneider'sche Membrane is further reduced.

In a further preferred embodiment of the The osteotome according to the invention is the proximal part as a spherical tree, especially designed as a wire ball tree. The middle part is designed as a hollow cylinder and the individual wires balls attached to it at the end are from the inside of the middle part extendable.

This ensures that the wire ball tree through single pressure on the handle of the distal end of the osteotome under the mucous membrane to be removed laterally and cranially spreads out and thereby detaches them from the bone.

Common alloys come as materials for the wire ball tree for surgical instruments but also biocompatible Plastic materials in question.

A preferred wire ball tree osteotome includes a proximal one Part with at least three, preferably five arranged on wires Balls.

As a particularly suitable osteotome for implantation purposes in the Dentistry has turned out to be one in which the proximal part as a balloon, in particular as an absorbable balloon is trained.

Such an osteotome is characterized in that the balloon from a hollow cylindrical middle part by filling with a fluid, especially air or a liquid, preferably physiological saline, is inflatable.

The particular advantage of a balloon osteotome is that Use of absorbable balloon envelopes, these to shape the Implant bed with simultaneous delimitation from the Schneiderian membrane and its protection can be used.

In addition, this balloon-assisted internal sinus lift particularly gentle and controlled for the Schneiderian membrane be performed.

On the one hand, it is principally used to inflate the proximal balloon possible, the distal part also as a balloon, especially with larger volume than the proximal balloon, though this double balloon procedure because of LaPlace's law is difficult to perform.

On the other hand, it has been found in practice that the proximal balloon better with a precision pump with a defined Pressure, e.g. B. with physiological NaCl under constant pressure control filled and thereby inflated.

Another preferred embodiment of the invention Osteotome is characterized in that the middle part is a Fixing device, in particular a bayonet lock for fixing the balloon envelope in a desired inflated state and / or Has position.

A preferred osteotome can also be characterized in that that there is a device for the defined separation of the balloon envelope in Form of an eccentrically mounted cutting plate on the proximal End. This has the advantage that the balloon with Augmentation mixture can be filled and after insertion the implant of the balloon in the maxillary sinus under the Schneiderian membrane can remain. Depending on the balloon material the balloon is then resorbed within several weeks.

However, the balloon does not necessarily have to be absorbable Material exist, but after forming the cavity between Corticalis and Schneiderian membrane and their detachment can the fluid can be sucked off again, e.g. B. about the sensory System with piston pump, the sagging balloon withdrawn and the other instruments described Bone mixture introduced, compacted and condensed.

The separation device for the balloon envelope is preferably through the middle part of the osteotome into the interior of the proximal balloon designed to be insertable.

It is also preferred that the distal portion of the osteotome unite Handle, in particular a nose, which is non-positively connected to the osteotome, causing the osteotome to rotate 360 ° is rotatable so that the surgeon has the instrument in each of them position you want.

The drill according to the present invention is suitable excellent for controlled and safe bone milling Preparation for the insertion of dental implants, which in the Maxillary sinus, but without destroying the Schneiderian membrane, must be anchored.

The pre-drill principle according to the invention can of course also in the Performing other surgical procedures, where it is advantageous to have different densities and thus Feel the resistance of tissues. Especially the Protection of endangered structures in the bones such as nerves and Vessels should be mentioned as another area of indication:

So there is during implantation in the distal area of the lower jaw the risk of injuring the mandibular nerve if the drill is closed penetrates deeply, resulting in loss of feeling and loss of function in the area of the lower lip and chin. The pilot drill can do this here Help locate vascular / nerve bundles as well as in the upper jaw the Schneiderian membrane.

In addition, in the special case of "dental Implantology "not only increases the requirement in the area of the maxillary sinus augment. Likewise, in the area of recoveries and Undercuts from the alveolar ridge and jaw shape may be beneficial to that Detect periosteum using the predrill according to the invention and build up bones there in the sense of an elevation. The The integrity of the periosteum guarantees success here.

If there is a lack of jaw body height in the lower jaw, level a submental augmentation is also advantageous.

Apart from medical applications, the inventive drill even in the technical field Find application when sensitive structures are found without destroying it, e.g. B. When drilling in multi-layer Structures such as B. sheathed lines, pipes and electrical lines in house walls, especially brick and Drywall.

The osteotome according to the present invention is suitable for non-destructive detachment of the Schneiderian membrane of the Maxillary sinus from the oral cavity, after pre-drilling with a implant bed pre-drills according to the invention.

The osteotomes according to the invention can also be used in the external Sinus lift can be used to advantage. The integrity of the Schneiderian membrane can be used with conventional external Sinus lift can be checked visually by the fact that these are at the The patient's nasal breathing is moving and with the nose closed bulges. Via the balloon osteotome with attached sensory system can be caused by breathing Pressure changes observed and also evaluated diagnostically become.

Further advantages and features of the present invention result themselves based on the description of exemplary embodiments as well based on the drawing.

It shows:

Fig. 1 is a Sinusliftkürette of the prior art;

Fig. 2 is a view of a dental implant (left) and of a commercial implant drill (right) from Friatec, Model "Frialit-2 Synchro", clamped in a contra-angle drive head with cooling medium supply from the top in the center of the milling machine;

Fig. 3 is a view of an implant bed pre-drill according to the invention (right), which is inserted into a commercially available contra-angle driving head with a retracted sensor tip and pressure build-up and pressure measurement system supplied from above, as well as a commercially available implant bed drill (center) and a dental implant (left);

Fig. 4 is a view of a Implantatbettvorbohrers according to the invention with retracted probe tip;

Fig. 5 is a view of an implant bed pre-drill according to the invention (right), which is inserted into a commercially available contra-angle driving head with the probe tip extended and the pressure build-up and pressure measurement system supplied from above, as well as a commercially available implant bed drill (center) and a dental implant (left);

Fig. 6 is a view of a Implantatbettvorbohrers invention with extended probe tip;

7 is a longitudinal section through an inventive Implantatbettvorbohrer with retracted probe tip.

Figure 8 is a longitudinal section through an inventive Implantatbettvorbohrer with extended probe tip.

Figure 9 is an overall schematic view of the drilling system according to the invention, partly as a sectional view of a drill according to the invention in drilling state just before it reaches the maxillary sinus side cortex, with external circuitry in a schematic representation.

Figure 10 is an overall schematic view of the drilling system according to the invention, partly as a sectional view of a drill according to the invention in the OFF state, by automatically shutting down the system when the probe tip suddenly permeates the maxillary sinus side cortex, with external circuitry in a schematic representation.

11 is a sectional view of an osteotome according to the invention with an eccentric plate as its proximal portion for detaching the Schneiderian membrane from the bony maxillary sinus floor, which is a prepared bone channel cranial guided below the Schneiderian membrane.

Figure 12 is a schematic plan view of the eccentric proximal plate. the eccentrically arranged plate expands laterally when turned in the direction of the arrow;

Fig. 13 shows a further embodiment of an osteotome according to the invention, wherein the proximal part is designed as a wire ball tree;

Figure 14 is a plan view of the proximal wire ball tree in ungespreiztem state (left) and in a spread-below the Schneiderian membrane state (right) to the lateral and cranial expansion.

Figure 15 is a sectional view of an osteotome according to the invention with ballonförmigem proximal portion and distal portion also ballonförmigem.

FIG. 16 is a sectional view of another embodiment of an osteotome according to the invention with ballonförmigem proximal portion, said balloon from the distal end is here filled with a physiological saline solution under pressure and volume control for cranial and lateral extension of the space below the Schneiderian membrane;

Figure 17 system according to the invention in an overall view of the instrument according to the order of use from right to left. Drills with extended probe tip; Osteotome sleeve with inflated proximal balloon; Implant bed drill and implant;

18 is a longitudinal section of an osteotome according to the invention with only partially inflated to the dimensional stability balloon-shaped proximal portion in the working position approximately level with the already broken maxillary sinus side corticalis.

FIG. 19 is a longitudinal section of an osteotome according to the invention with a fully inflated balloon-shaped proximal portion in the working position considered cranial behind the maxillary sinus side cortex under the Schneiderian membrane, whereby this is extended at the same time laterally and cranially;

Fig. 20 is a schematic representation of the filling of using the osteotome of FIG. 18 and 19 prepared implant bed bone mixture and longitudinal section through the outer sleeve, maxillary sinus floor and disposed below the Schneiderian membrane resorbable balloon after removal of the osteotome of FIG. 18 and 19; and

Fig. 21 is a sectional view of the resorbable balloons in the end position after the complete filling with bone mixture and instrument for defined separation of the balloon envelope.

Fig. 1 shows a prior art sinus curette for pushing away the Schneiderian membrane with a spoon-shaped end on both sides in the manner of a spatula.

Fig. 2 shows a modern implant system "Frialit-2 Synchro" from Friatic. left: implant; right hand contra-angle drive head with clamped implant bed drill with coolant supply from above into the center of the milling machine, as is currently used for the implantation of dental implants.

Implants are metal pins that go directly into the jawbone be cemented. Then the so-called Superstructure set, an artificial tooth, similar to one normal crown.

Fig. 3 shows a made by the inventor of the present invention converted implant system formerly "Biolox" from field mill AG, left: implant; Middle: implant bed drill. In the right half of FIG. 3, a drill 1 according to the invention - in the example an implant bed pre-drill - is shown, which is inserted into a commercially available contra-angle drive head 2 with the probe tip 3 retracted and the pressure build-up and measurement system 4 fed in from above.

The sensor tip 3 is always in the retracted state when the resistance of the processed bone tissue is greater than or equal to the threshold force preset by means of an electronic control (not shown). This threshold force is generated on the implant bed pre-drill by applying a fluid pressure inside the implant bed pre-drill. In the example, physiological NaCl solution is used as the fluid. The saline solution is pressurized with the help of a computer-controlled precision pump. The threshold value and actual value data of the pressure applied to the sensor tip 3 are evaluated by a computer and displayed graphically in real time on a monitor.

Fig. 4 shows the drill of Fig. 3 in an enlarged view.

FIG. 5 shows the implant bed pilot drill 1 according to the invention with the probe tip 3 extended, and FIG. 6 shows the implant bed pilot drill of FIG. 5 in an enlarged view.

In FIGS. 5 and 6 of the 'quick stop state "is shown of the drill. Suddenly, during the drilling process, the resistance of the tissue lying in front of the probe tip 3 collapses, e.g. B. penetration of the cortical side of the maxillary sinus, the probe tip 3 is moved out of the drill 1 due to the greater internal pressure and thereby decouples the drill 1 mechanically from the drive and on the other hand the power is immediately switched off and the drill is actively braked so that it this stops it in time so that it cannot penetrate the Schneiderian membrane. As a result, the drill system according to the invention is independent of the speed of reaction of the surgeon and it is avoided that although the surgeon withdraws the instrument when noticing the lower resistance, it nevertheless penetrates deeply into the maxillary sinus through the drill outlet and thereby penetrates the Schneiderian membrane.

Fig. 7 shows a detailed longitudinal section through an inventive drill 1 in the loaded state, that is, with retracted probe tip 3. The probe tip 3 is mechanically coupled in the loaded and thus retracted state with the pilot drill housing 5 , so that it rotates with the pilot drill tip 10 when drilling.

In the example, the mechanical coupling takes place in that the distal end 6 of the probe tip 3 is designed as an external hexagon which engages in a drive part 7 of the implant bed pilot drill 1 designed as an internal hexagon in the loaded state.

A defined threshold pressure is built up via the pressure build-up and pressure measurement system 4 by means of physiological NaCl solution, which pressure is applied via a cannula 8 angled at its distal end, which leads through a shaft 9 of the implant bed pilot drill 1 into its interior and opens into the hexagon-shaped drive part 7 , If the probe tip 3 is in dense tissue, which has a resistance force that is greater than or equal to the threshold force (internal pressure), the external hexagon of the distal end 6 of the longitudinally displaceable probe tip 3 maintains the equilibrium with the internal pressure lying on the drive hexagon 7 , so that the probe tip 3 and Rotate the pre-drill tip 10 together around the cannula 8 .

The internally guided cannula 8 is sealed against the outer wall 11 of the pilot drill housing 5 by means of a seal 12 . Sealing in the proximal direction is carried out by means of a seal 13 , which is arranged in a ring around the probe tip 3 .

The shaft 9 of the implant bed pilot drill 1 is screwed to the pilot drill housing 5 via a thread 14 .

The corresponding implant bed pilot drill at rest is shown in FIG. 8:

As soon as the probe tip 3 penetrates into less dense medium, the pressure built up via the supplying sensory pressure build-up system 4 discharges and the probe tip 3 moves forward faster (see FIG. 8) than the pilot drill housing 5 . The sensor tip 3 is thus decoupled from the rotary movement because the internal and external hexagon are separated from one another, the pressure in the sensory pressure build-up system 4 drops and triggers the standstill of the rotary movement of the pilot drill housing 5 and via a control system (not shown in FIGS. 7 and 8) thus the standstill of the drill bit 10 .

To further clarify the mechanical coupling and decoupling of the drive internal hexagon 6 and external hexagon 7 of the sensor tip 3 , the cross sections of both parts 6 and 7 along the section lines AA 'and BB' are shown in FIGS . 7 and 8.

Using x-rays, the surgeon can classify the density of the bone and calibrate and adapt the sensory pressure build-up system 4 by presetting the initial pressure in the sensory system.

In FIGS. 9 and 10 is shown the overall system in a schematic representation, Fig. 9 shows the Implantatbettvorbohrer 1 and its retracted probe tip 3 in the working state, the proximal end of the probe tip 3 is located just before the maxillary sinus side corticalis.

Fig. 10 shows the Implantatbettvorbohrer 1 in the tripped standstill with extended probe tip 3, which is already inside the maxillary sinus.

It is preferred that the drill drive motor M1 can be actuated by means of a foot switch A and the pump motor M2, which in the example is a tubular motor, can be actuated by means of a foot switch B. The relevant threshold pressure and actual value data are graphically displayed on a monitor 21 .

The pressure within the pressure build-up and pressure measurement system 4 is detected via a pressure sensor P. If it falls below a predetermined threshold value, the controller R immediately switches off the power supply for the drive motor M1 of the implant bed pilot drill 1 . In addition, the drive motor M1 is braked inductively in the example, so that the implant bed pilot drill 1 comes to a standstill almost immediately.

FIG. 11 shows an osteotome 30 which is guided through a bone canal prepared with the implant bed pre-drill 1 and serves to detach the Schneiderian membrane 31 from the bony maxillary sinus floor 32 . The osteotome 30 has an eccentrically arranged plate 34 at its proximal end 33 .

The osteotome 30 is advanced as far as the Schneiderian membrane 31 and this is detached in that a rotatable plate 34 that can be operated via the eccentrically located axis from the other (distal) end 35 extends the surrounding space 36 laterally. When pressure is applied to the distal end 35 , the space 36 is widened cranially under the Schneiderian membrane.

The top view in FIG. 12 illustrates that when the eccentrically mounted plate 34 rotates, the space 36 is expanded laterally.

In Figs. 13 and 14 a further embodiment of osteotome 40 is shown having a proximal portion 43 of a wire harness ball 44, are arranged on wires 45 in which balls 46.

This embodiment of the osteotome 40 according to the invention is able to expand the Schneiderian membrane 31 laterally and cranially at the same time in one operation by spreading the wire ball tree 44 three-dimensionally under the Schneiderian membrane 31 by a single pressure on the distal end 46 ,

The spreading of the wire ball tree 44 laterally and cranially is shown again in FIG. 14 as a top view.

Due to the balls 46 , which are five in the present example, the Schneiderian membrane 31 is not injured and is carefully detached from the bony floor of the maxillary sinus 32 .

Fig. 15 shows a sectional view of another embodiment of the invention with osteotome 50 ballonförmigem proximal portion 53 and distal portion 55 also ballonförmigem.

In the example, the proximal balloon 54 is inflated with physiological saline solution by compressing the distal balloon 55 , which is connected to it hydrostatically, under the Schneiderian membrane 31 , resulting in a simultaneous lateral and cranial expansion.

An osteotome 50 with a balloon-like elastic swelling at the end of the work helps to avoid the risk of injury to the Schneiderian membrane 31 by cushioning the forces which are necessary to further process the surrounding bone.

Here, the Schneiderian membrane 31 is detached by increasing the size of the balloon-like elastic expansion 54, primarily by further filling with physiological saline.

Furthermore, by means of a balloon osteotome 50, an optimal adaptation of the shape of the working end 53 to the shape of the cavity 36 which occurs when the Schneiderian membrane 31 is detached from the bone 32 and thus an optimal pressure distribution can be achieved.

In addition, a constant control of the pressure in the balloon-like expansion 54 and a constant control of the increase in volume in the balloon-like expansion 54 can be carried out in order to be able to estimate the size of the new bone space 36 created.

With all the advantages described, which the double balloon osteotome 50 offers, the filling by means of a distal balloon 55 is still somewhat unwieldy in practice.

Therefore, the applicant and inventor of the present application have developed yet another osteotome 60 , which is shown in FIG. 16. The osteotome 60 has a balloon 64 only on its proximal part 63 . At its distal end 65 , the proximal balloon 64 is inflated as required by controlled inflation with physiological NaCl solution by means of a precision pump ( not shown in FIG. 16) after positioning under the Schneiderian membrane 31 under optimally controllable conditions.

The balloon 64 is pushed by means of a sleeve 70 on its shaft 66 over the osteotome 60 and at the same time fastened. The balloon 64 is then inflated via the pressure-building portion of the sensory system 4 by means of a physiological NaCl solution.

If necessary, the osteotome 60 can perform longitudinal oscillatory movements, making it easier to drive it into the bone in the cranial direction and making it easier to break the cortical bone on the jaw cavity side.

The advantage of the balloon osteotome 60 lies particularly in the avoidance of pressure peaks which could initiate tearing of the maxillary sinus mucosa.

Angled embodiments of those shown by way of example Osteotomes simplify handling, especially when tapping Bone preparation enormous.

From the handling difficulties described above with double balloon osteotomes 50 , the inventor therefore favors the osteotome 60 , the proximal balloon 64 of which is filled mechanically by means of a precision pump under constant control by highly sensitive pressure and volume measurement.

This automated procedure relieves the operator. In front especially the display and documentation of the pressure and volume This gives parameters on the monitor with simultaneous recording by EDP Surgeon safety during and after treatment, provided forensic questions should be clarified.

Fig. 17 shows system of the invention in an overall view of the instrument according to the order of use from right to left: Implantatbettvorbohrer 1 with extended probe tip 3; Osteotome sleeve 70 with inflated proximal balloon 64 ; Implant bed drill and implant.

In Fig. 18 a longitudinal section of the preferred embodiment is shown of an osteotome 60th The balloon-shaped proximal part 64 is only partially inflated for dimensional stability. In the working position shown, the balloon 64 is located approximately at the level of the cortical bone that has already broken open. Balloon 64 is filled with a physiological saline solution via cannula 68 by means of a precision pump.

The angled cannula 68 is sealed against the balloon envelope 71 by means of a seal 69 . The balloon envelope 71 is thus located between the inner wall of the outer sleeve 70 and the osteotome outer wall 72 .

In the example, the balloon envelope 71 is fixed by means of a bayonet lock 73 and can optionally be adjusted.

The shaft 74 of the osteotome 60 can perform a striking movement.

Fig. 19 shows a longitudinal section of an osteotome 60 according to the invention with a fully inflated balloon-shaped proximal portion 64 in two different Aufblähzuständen A and B. The work position is - viewed from the ventral side - behind the maxillary sinus side cortical bone 32 below the Schneiderian membrane 31, whereby these lateral simultaneously and expanded cranially. The balloon is filled further 64 from the state A to the state B, so the balloon 64 inflates to the dashed balloon 64 'and expands the Schneiderian membrane 31 from the state A to the diaphragm 31 also shown in phantom Schneiderian 'in condition B.

Fig. 20 is a schematic illustration showing the filling of using the osteotome 60 shown in FIG. 18 and 19 prepared implant bed bone mixture and longitudinal section through the outer sleeve 70, maxillary sinus floor 32 and below the Schneiderian membrane 31 arranged resorbable balloon 64 after removal of the Osteotome 60 . In this case, a pasty bone mixture 81 is filled into the balloon 64 via a fixing instrument 82 with a funnel function at the same time, using a darning instrument 80 .

After the filling process has ended, the resorbable balloon envelope 71 is separated in a defined form by means of a cutting device 90 . The cutting device 90 has at its distal end a knurled screw 91 for actuating the eccentrically arranged cutting plate 92 . The cutting device 90 also has a nose 93 , by means of which the cutting device 90 can be guided through 360 °.

The implant is then introduced into the resulting artificial bone bed in a known manner and finally provided with the superstructure. Reference number list 1 drill / implant bed pilot drill
2 contra-angle power car
3 sensor tip
4 pressure build-up and measurement system
5 pilot drill housings
6 External hex-shaped distal end of the probe tip
7 Hexagon-shaped drive part
8 cannula
9 shaft of the implant bed pilot drill
10 pilot drill tip
11 outer wall of the pilot drill housing
12 seal
13 seal
14 threads
30 plate osteotome
31 Schneiderian membrane
32 corticalis on the jaw cavity side
33 proximal end of the osteotome 30
34 plates
35 distal end
36 room
40 wire ball tree osteotome
43 proximal part
44 wire ball tree
45 wire
46 balls
50 double balloon osteotome
53 balloon-shaped proximal part
54 proximal balloon
55 balloon-shaped distal part
60 balloon osteotome
63 proximal part
64 proximal balloon
65 distal end
66 shaft
68 cannula
69 seal
70 sleeve
71 balloon envelope
72 outer wall of the osteotome
73 bayonet catch
74 shaft
80 darning instrument
81 mixed bone
82 fixing instrument
90 cutting device
91 thumbscrew
92 cutting plates
93 nose

Claims (28)

1. drill, in particular for milling bones in preparation for the insertion of dental implants, which is provided as an insert in a drill head ( 2 ) equipped with drive and coolants,
characterized in that
the drill ( 1 ) has an outer drill tip ( 10 ) and inside which a coaxial sensor tip ( 3 ) is arranged, which is non-positively connected to the rotatable outer drill tip ( 10 );
the probe tip ( 3 ) can be pushed out in the axial direction from the tip of the drill ( 1 );
the probe tip ( 3 ) is subjected to a predetermined adjustable threshold force; and
the sensor tip ( 3 ) emerges from the outer drill tip ( 10 ) when falling below a resistance force directed against the threshold force and is thereby decoupled from the rotational movement of the outer drill tip ( 10 ). 2. Drill according to claim 1, characterized in that the sensor tip ( 3 ) with the outer drill tip ( 10 ) via a male / female plug connection ( 6 , 7 ) is non-positively connected. 3. Drill according to claim 2, characterized in that the sensor tip ( 3 ) at the end which is connected to the outer drill tip ( 10 ) has an external hexagon ( 6 ) and inside the outer drill tip ( 10 ) has a corresponding internal hexagon ( 7th ) is provided. 4. Drill according to one of claims 1 to 3, characterized in that the threshold force of the sensor tip ( 3 ) is carried out by means of a pressurization by means of a fluid. 5. Drill according to claim 4, characterized in that the fluid is a liquid, in particular is physiological saline. 6. Drill according to one of claims 1 to 5, characterized characterized in that the pressurization by means of a piston pump. 7. Drill according to one of claims 1 to 6, characterized in that at least one sensor device is provided for detecting the actual state of the pressure within the fluid inside the outer drill tip ( 10 ). 8. Drill according to claim 7, characterized in that a circuit is provided which registers a pressure drop detected by the sensor device (p) and actuates a switch which switches off and / or brakes the drive of the drill ( 1 ). 9. Drill according to one of claims 1 to 8, characterized in that the drive motor (M1) and / or the motor (M2) for pressurizing the sensor tip ( 3 ), in particular piston pump motor, in particular by means of foot switches (A, B), can be remote-controlled , 10. Drill according to one of claims 1 to 9, characterized in that the threshold force and the actual state of the resistance force are shown on a display device, in particular a monitor ( 21 ). 11. Osteotome for the non-destructive detachment of a layer of tissue from a bone tissue from the bone side after penetration of the bone, with:
a distal portion for guiding the osteotome ( 30 ; 40 ; 50 ; 60 );
a proximal portion for detaching the tissue layer ( 31 ); such as
a middle part that separates the distal part from the proximal part. 12. Osteotome according to claim 11, characterized characterized in that the distal part is a handle, especially a roughened handle, is preferably an angled handle. 13. Osteotome according to claim 11 or 12, characterized in that the proximal part ( 33 ) is a plate ( 34 ) arranged at an angle of approximately 90 ° to the longitudinal axis of the central part, which plate is attached to the central part so as to be eccentrically movable. 14. Osteotome according to claim 13, characterized in that the plate ( 34 ) is attached to the central part such that its outer diameter is at most as large as the outer diameter of the central part. 15. Osteotome according to one of claims 13 to 14, characterized in that the plate ( 34 ) is formed convex proximally. 16. Osteotome according to one of claims 11 or 12, characterized in that the proximal part ( 43 ) is designed as a spherical tree ( 44 ). 17. Osteotome according to claim 16, characterized in that the ball tree ( 44 ) is designed as a wire ball tree;
the middle part is designed as a hollow cylinder; and
the individual wires ( 45 ) with balls ( 46 ) attached to them at the end can be pushed out from the interior of the central part. 18. Osteotome according to claim 17, characterized in that the proximal part ( 44 ) comprises at least three, preferably 5 balls ( 46 ) provided on wires ( 45 ). 19. Osteotome according to claim 11 or 12, characterized in that the proximal part is designed as a balloon ( 54 ; 64 ), in particular as an absorbable balloon ( 54 ; 64 ). 20. Osteotome according to claim 19, characterized in that the balloon ( 54 ; 64 ) is inflatable from a hollow cylindrical middle part by filling with a fluid, in particular air or a liquid, preferably physiological saline. 21. Osteotome according to claim 19, characterized in that the distal part is also designed as a balloon ( 55 ), in particular with a larger volume than the proximal balloon ( 54 ). 22. Osteotome according to one of claims 19 to 20, characterized in that the central part has a fixing device ( 73 ), in particular a bayonet lock for fixing the balloon envelope ( 71 ) in a desired position. 23. Osteotome according to claim 22, characterized in that it has a cutting device ( 90 ) for the defined separation of the balloon envelope ( 71 ) in the form of an eccentrically mounted cutting plate ( 92 ) at the proximal end. 24. Osteotome according to claim 23, characterized in that the cutting device ( 90 ) for the balloon envelope ( 71 ) through the central part of the osteotome ( 60 ) in the interior of the proximal balloon ( 64 ) can be inserted. 25. Osteotome according to one of claims 19 to 24, characterized in that in the osteotome ( 60 ) a cutting device ( 90 ) can be inserted, which has a handle, in particular nose, which is non-positively connected to the cutting device ( 90 ), whereby the cutting device ( 90 ) can be rotated through 360 °. 26. Use of a drill according to one of claims 1 to 10 for bone milling in preparation for the insertion of dental implants, which have to be anchored in the maxillary sinus, but without destroying the Schneiderian membrane ( 31 ). 27. Use of an osteotome according to one of claims 11 to 25 for non-destructive detachment of the Schneiderian membrane ( 31 ) of the maxillary sinus from the oral cavity, after predrilling with a drill ( 1 ) according to one of claims 1 to 10. 28. Use of a drill according to one of the Claims 1 to 10 for technical drilling in multilayer structures in which one certain structure must not be damaged.